AudioNervosa
Systemic Development => Amplification and Preamplification => Tubes => Topic started by: BobM on September 23, 2013, 11:13:45 AM
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What is your favorite?
I've tried a few ...
Sovetek's - actually not bad at all, but a a little 2 dimensional and not quiote as dynamic as others
Mullards - beautiful midrange but tubey bottom end
Telefunkens - beautiful top end but a bit thin
Radiotechnique - same as the Tele's, beautiful top end but no bass
RCA Clear Tops - generally pretty decent, dynamic and extended but I detect a little bit of a metallic sheen to them
Sylvania - haven't heard these, but are supposed to be along the lines of the RCA clear tops from what I read
Baldwin - These are my favorite affordable 12AU7 (black plates), manufactured by Raytheon, extension, dimensional, dynamics, with a touch of richness
Amperex - still haven't heard any of these, generally expensive but supposed to be worth it
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Shuguang $7. Cleanest, clearest of any I have heard, full sound without any tubiness, low distortion all around. More detailed than vintage tubes. They come stock in Eastern Electric gear.
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For the equipment I have that uses AU7's, RCA Black Plates are what I prefer (of those I will choose to pay for...) Baldwins are similar but to me, not quite as balanced - a TAD more forward in the mids but a TAD more shimmer up top. Both have a nice richness and solid bottom end.
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My experience with the 12AU7s are limited to use as drivers and pre-amp tubes in my Rogue Cronus Magnum and as the output tube in an Eastern Electric DAC and DAC Plus (both modded). (What works best in my system is NOS Mullard drivers, RT pre-amp and DAC tubes.)
That said, I have the same impression of most of the tubes you've listed, Bob, but what I hear differs in a few respects as follows:
Radiotechnique (1965 vintage, 6189 version): my favorite. Beautifully balanced from top to bottom, three dimensional, and resolving, with very nice tonal accuracy.
The Amperex are very well balanced and perhaps even more resolving, with a beguiling airiness to them but perhaps lack a little weight compared to the RT and NOS Mullards. The latter I also like but I agree that there is a touch of tubeyness to the bass
The Sylvanias are similar to the RCA Cleartops but not quite as bright on top. The GE 5814 is also similar but even better balanced tonally than the Sylvania.
The Raytheon/Baldwin black plates are definitely the best buys around and also just as you describe. The RCA black plates are similar.
To me the Shuguang are good but a touch clinical/not rich enough, the EH are muddy, the new Tung-Sol and new Mullard un-impressive (don't remember why), the new Genalex not any better than the new Mullards.
I actually like the JJ ECC82 short plate (the ECC 802 long plates are a little noisier) the most out of the new production. Well balanced and warm, if not particularly resolving. Rogue uses them as standard equipment in their gear. Jim McShane, on the other hand, doesn't think they're reliable (I've had no problems though I've only used them for a few to several months).
NOS Tung-Sol are warm and therefore easy to listen to but have a thickness to them that becomes annoying after a while. Same with Tungsram.
IMS, IMHO, blah, blah, blah. :thumb:
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Just curious... has anybody tried these?
SYLVANIA CONN 12AU7 ECC82 VACUUM TUBES LONG PLATE MATCHED PAIR SWEET TONE 1961
I bought a pair as backups to my EE Minimax DAC for under $15.00 shipped.
SN
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My new PrimaLuna Dialogue Premium preamp uses these...
Anyone know what stock 12AU7 they use ???
It sounds fine to me out of the box..but I may want to experiment with different ones when its time to re-tube.
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Are Raytheon/Baldwin gray plates as good as the Raytheon/Baldwin black plates???
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you won't know until you try, but I KNOW the black plates are very good. Check out this thread
http://forums.stevehoffman.tv/threads/steve-could-you-tell-us-your-ranking-of-the-12au7s.131152/ (http://forums.stevehoffman.tv/threads/steve-could-you-tell-us-your-ranking-of-the-12au7s.131152/)
and Brent Jesse for a reasonably priced supply of them
http://forums.stevehoffman.tv/threads/steve-could-you-tell-us-your-ranking-of-the-12au7s.131152/ (http://forums.stevehoffman.tv/threads/steve-could-you-tell-us-your-ranking-of-the-12au7s.131152/)
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Just curious... has anybody tried these?
SYLVANIA CONN 12AU7 ECC82 VACUUM TUBES LONG PLATE MATCHED PAIR SWEET TONE 1961
I bought a pair as backups to my EE Minimax DAC for under $15.00 shipped.
SN
I happened upon a Conn organ at a thrift and managed to convince the manager to sell me just the electronics. Each key had a 12AU7 - needless to say, I ended up with over 100 of the tubes and they all tested fine so they've been my go-to AU7 ever since. They are Sylvania Cleartops w/green lettering and sound clean, clear and quiet. I favorite variant is the GE 5814a black/dark gray plates but the ones made by RCA and Sylvania are quite close in tone. By comparison, the cleartops are slightly warmer than the 5814's but since 12AU7's and their variants are plentiful and cheap, you can roll with abandon and still keep the bank intact. For what its worth, I've used these tubes in a DAC, phono pre and preamp/driver stages in some vintage amps (guitar and audio).
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I have been using 12AU7 tubes forquite some time as most of my gear is designed around this tube. My top favorites are:
Baldwin -
Sophia Electric -
Sylvania -
Siemens-
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I agree with a lot of the points here. JBryan's assessment on the Sylvania 5814 is spot on. I acquired 2 pairs of them at a good price and they aren't going anywhere. IME I prefer the black plates sonically to the grey plates. I've always had blah sounding results with grey plate white label GE 12AU7s and grey plate RCA 12au7 type tubes from the 70s. I guess I've just had bad luck with the ones I've gotten.
One set of tubes I regret selling were the Hewlett Packard orange labeled 5963 tubes. They were sweet sounding.
Another 12AU7 type tube that I can't find is a yellow labeled Westinghouse ECC82 that has a smaller grey plate but has all these rods I hadn't seen in a vintage tube before. I'm attaching a picture just in case you tube vets have seen it before.
As for new stock 12AU7 tubes I've only listened to the Penta Labs 12AU7s from Doug's tubes and EH 12AU7 tubes that came stock with a headphone amp. EH was thin sounding and the Penta Labs were ok.
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Thanks sleepy. The Westinghouse is another one of my favs. Forgot about that one. I have 6 pair at one time. One pair was in one of my preamps and the other got shattered in the flood :(
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After trying a number of 12au7s and its variants in my Hovland HP-100 line stage, I finally settled on the Amperex PQ two star 7316 Holland D-getter. Sound just seems to have "locked in" and blended with the other tubes and circuitry.
Agree with BobM's assessments, except for the Radiotechnique, which I have not heard.
Tried the Siemens & Halske Ecc82 chrome /silver /nickel plate and the Mullard 10M Master Series 12au7 B6K2 standard pin. They didn't mate well, so stick with the less expensive RCA 12au7 black plate angled D getter or the RCA JRC-6189 black plate triple mica square getter for the more solid midrange vocals or the richer sounding Ken-Rad labeled GE 12au7 long black plate with angled, raised thick bar D getter.
The inexpensive but elusive Sperry Gyroscope 12au7 military grade horseshoe bar D getter with brushed glass mark code T6 SPL 823623 was a good all-around tube I used for almost a year.
Bottom line : the expensives are not necessarily better. Haven't heard the Westinghouse, Shuguang, JJ, 5814 or Tung Sol.
Jason/
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You guys have me going "to hell in a hand-basket"... I just bought these for $13.10 shipped.
Lot of (2) 12AU7 Baldwin long black plates (Raytheon) tubes.
These were tested on a Hickok 533a which calls for {2200/2200} for NOS tube micromhos @150v Hickok plate voltage:
Tube 1 tested at {2025-1975} - 92%-90%
Tube 2 tested at {2150-2000} - 98%-91%
These were also tested on a custom bench tester which calls for {2200/2200} for NOS tube micromhos @250v tube data sheet plate voltage:
Tube 1 tested at {1957-1950} - 89%-89%
Tube 2 tested at {2093-1951} - 95%-89%
All this by a guy who didn't have a single tube in his system for 41 of the past 42 years of stereo ownership!
SN
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You guys have me going "to hell in a hand-basket"... I just bought these for $13.10 shipped.
Lot of (2) 12AU7 Baldwin long black plates (Raytheon) tubes.
These were tested on a Hickok 533a which calls for {2200/2200} for NOS tube micromhos @150v Hickok plate voltage:
Tube 1 tested at {2025-1975} - 92%-90%
Tube 2 tested at {2150-2000} - 98%-91%
These were also tested on a custom bench tester which calls for {2200/2200} for NOS tube micromhos @250v tube data sheet plate voltage:
Tube 1 tested at {1957-1950} - 89%-89%
Tube 2 tested at {2093-1951} - 95%-89%
All this by a guy who didn't have a single tube in his system for 41 of the past 42 years of stereo ownership!
SN
Ah to tube or not to tube is the question. When tubing remember that the caps used will influence the tube used. IMO that is the synergy we go after.
For example when V-caps are used as output caps the RCA brand works wonders. When Duelund CAST is used the GE tubes are better.
Just keep trying all ya can. Have fun amigo.
charles
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And there are as many opinions on caps as there are on tubes - maybe more. Charles just told of a couple options. In MY preamp, Ven Haus Teflons for coupling caps and OIMP's for output caps does the trick.
YMMV
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link=topic=4766.msg61952#msg61952 date=1380563629]
Ah to tube or not to tube is the question. When tubing remember that the caps used will influence the tube used. IMO that is the synergy we go after.
For example when V-caps are used as output caps the RCA brand works wonders. When Duelund CAST is used the GE tubes are better.
Just keep trying all ya can. Have fun amigo.
charles
Charles is on point here: it's very true.
Also caps, IME, make at least as much difference as tubes, and often more.
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So do power cords ... and interconnects ... and speaker cables ... and footers ... and salt lamps in the room (well maybe not so much). I think most of us have experienced how just about anything can influence the sound. And blending all these things into a sound that YOU like and appreciate can go through quite a few iterations and configurations, and may not ever get "perfect".
That being said - can we get back on 12UA7 topic and tubes that you have experience with and like?
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I want to add one more thing that I find influences our systems that many don't take into consideration. Being in the North East where our weather and humidity changes by the hour, we find that the sound of our systems can change quickly with different humidity levels. (thicker air). A hot humid or rainy damp day causes the sound to be muffled and dull unless our listening room is temperature controlled with an air conditioner.
If you don't beleive me, leave your air off on the next hot humid day (if we see any more days like that) :?
That being said - can we get back on 12UA7 topic and tubes that you have experience with and like?
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My new PrimaLuna Dialogue Premium preamp uses these...
Anyone know what stock 12AU7 they use ???
It sounds fine to me out of the box..but I may want to experiment with different ones when its time to re-tube.
Dick Olsher said in his review of the PrimaLuna DiaLogue Premium Integrated Amp in the Absolute Sound (May/June 2013) that the stock 12AU7 is a good-sounding tube but found a weakness later, an assertive upper mid-range.
If you find that to be the case, then a warmer sounding tube may be needed.
The DiaLogue Premium preamp uses 6 12AU7s. Note that you need not use 6 tubes of the same make or model, but can mix and match 12AU7s of different manufacturers.
Jason/
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It is rare that you find a reviewer who will roll tubes during a review. Generally they are supposed to test and evaluate the equipment just as it comes from the manufacturer. What we can know from that, is if they like it stock, then it likely can be improved with a little judicious tube rolling.
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D.O. is reviewing the integrated amp not the preamp...I do not notice an assertive upper mid-range in my system.
I find this preamp is adept at dynamic changes without getting aggressive. Of course its all system dependent your results may vary.
When the time comes to replace tubes I am interested in improving on it's virtues if possible.
Speaking of replacement, the manual indicates a tube life of 5,000 to 10,000 hrs. sounds a bit optimistic to me.
Greg
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Speaking of replacement, the manual indicates a tube life of 5,000 to 10,000 hrs. sounds a bit optimistic to me.
This does not have to be too far out of reach. It is very possible to design a preamp circuit that allows this kind of tube life. Our Musica Bella preamp circuit is also design in such a way that we rate tube life as high as 10,000 hrs.
I have one of my original preamps that is almost 10 years old that still has the original tubes in it. Not sure of the hours but I would guess over 5k-6k hours.
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Speaking of replacement, the manual indicates a tube life of 5,000 to 10,000 hrs. sounds a bit optimistic to me.
This does not have to be too far out of reach. It is very possible to design a preamp circuit that allows this kind of tube life. Our Musica Bella preamp circuit is also design in such a way that we rate tube life as high as 10,000 hrs.
I have one of my original preamps that is almost 10 years old that still has the original tubes in it. Not sure of the hours but I would guess over 5k-6k hours.
Well if that's the case, I will not feel so bad about leaving it on the better part of the day.
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I leave my preamps on 24/7 for a few days at a time. Unless there are real expensive tubes in it or if it has a tube power supply. Same for my hybrid amps as the tube input stage is a low voltage design. I do turn the output stage off but leave its power supply on all the time. (A benefit of Class D)
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Greg said..."Speaking of replacement, the manual indicates a tube life of 5,000 to 10,000 hrs. sounds a bit optimistic to me."
Tube life is very dependent on the circuit and varies greatly by the manufacturer - both the unit's and tube's. I have a Scott 222c in a 2nd system that has been used almost daily for over 15 years and it still has the original tubes that were installed in 1961. I have no idea how much the original owner used it but by my calculations, I have put about 15-16K hours on these Telefunkens (12AX7 and 7189) and last I checked (actually Terry DeWick checked 'em) they still test strong.
I also have a DAC with tube output stage and the Tele 12AX7's I installed back in 2002 have been either 'On' or in 'Standby' ever since and they show no signs of wear yet. Of course, now that I've said this, they'll all catastrophically fail this afternoon....
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I guess a couple reasons you are getting so long life with your Scott. One..... NOS tubes were built much more rugged than today's tubes. Two.... The older gear does not stress tubes like much of today's equipment does. Combine these two together and you may never have to replace those tubes again.